Magic Beacons and Magic Bullets: The Medical Applications of Functional Nanoparticles

Most envisaged future medical applications use nanoparticles that are programmed to individually perform a function, thus conforming to the definition of evolutionary nanotechnology given in the introduction, and this chapter is devoted to these. The chapter emphasizes the multidisciplinary nature of nanotechnology encompassing physics, chemistry, biology, engineering, and medicine. In nanoparticle-based medical applications, the particles are programmed to locate specific types of cells and then either perform some action to kill the cell (magic bullets) or show up with a very high sensitivity using an external diagnostic probe such as magnetic resonance (MRI) or ultrasound imaging (magic beacon). Any particle that would be used for hyperthermia will be smaller than 100 nm and thus would be a single magnetic domain. On re-imaging the region, any remaining nanomaterials will then report on how effective the treatment has been. This combination of diagnosis and therapy has been labeled “theranostics”. Controlled Vocabulary Terms biomedical MRI; hyperthermia; nanosensors; ultrasonic imaging